methods/https.cc

   1 //-*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: http.cc,v 1.59 2004/05/08 19:42:35 mdz Exp $
   4 /* ######################################################################
   5
   6    HTTPS Acquire Method - This is the HTTPS acquire method for APT.
   7
   8    It uses libcurl
   9
  10    ##################################################################### */
  11                                                                         /*}}}*/
  12 // Include Files                                                        /*{{{*/
  13 #include <config.h>
  14
  15 #include <apt-pkg/fileutl.h>
  16 #include <apt-pkg/acquire-method.h>
  17 #include <apt-pkg/error.h>
  18 #include <apt-pkg/hashes.h>
  19 #include <apt-pkg/netrc.h>
  20 #include <apt-pkg/configuration.h>
  21 #include <apt-pkg/macros.h>
  22 #include <apt-pkg/strutl.h>
  23 #include <apt-pkg/proxy.h>
  24
  25 #include <sys/stat.h>
  26 #include <sys/time.h>
  27 #include <unistd.h>
  28 #include <stdio.h>
  29 #include <iostream>
  30 #include <sstream>
  31 #include <ctype.h>
  32 #include <stdlib.h>
  33
  34 #include "https.h"
  35
  36 #include <apti18n.h>
  37                                                                         /*}}}*/
  38 using namespace std;
  39
  40 struct APT_HIDDEN CURLUserPointer {
  41    HttpsMethod * const https;
  42    HttpsMethod::FetchResult * const Res;
  43    CURLUserPointer(HttpsMethod * const https, HttpsMethod::FetchResult * const Res) : https(https), Res(Res) {}
  44 };
  45
  46 size_t
  47 HttpsMethod::parse_header(void *buffer, size_t size, size_t nmemb, void *userp)
  48 {
  49    size_t len = size * nmemb;
  50    CURLUserPointer *me = (CURLUserPointer *)userp;
  51    std::string line((char*) buffer, len);
  52    for (--len; len > 0; --len)
  53       if (isspace(line[len]) == 0)
  54       {
  55          ++len;
  56          break;
  57       }
  58    line.erase(len);
  59
  60    if (line.empty() == true)
  61    {
  62       if (me->https->Server->Result != 416 && me->https->Server->StartPos != 0)
  63          ;
  64       else if (me->https->Server->Result == 416 && me->https->Server->Size == me->https->File->FileSize())
  65       {
  66          me->https->Server->Result = 200;
  67          me->https->Server->StartPos = me->https->Server->Size;
  68          // the actual size is not important for https as curl will deal with it
  69          // by itself and e.g. doesn't bother us with transport-encoding…
  70          me->https->Server->JunkSize = std::numeric_limits<unsigned long long>::max();
  71       }
  72       else
  73          me->https->Server->StartPos = 0;
  74
  75       me->Res->LastModified = me->https->Server->Date;
  76       me->Res->Size = me->https->Server->Size;
  77       me->Res->ResumePoint = me->https->Server->StartPos;
  78
  79       // we expect valid data, so tell our caller we get the file now
  80       if (me->https->Server->Result >= 200 && me->https->Server->Result < 300)
  81       {
  82          if (me->https->Server->JunkSize == 0 && me->Res->Size != 0 && me->Res->Size > me->Res->ResumePoint)
  83             me->https->URIStart(*me->Res);
  84          if (me->https->Server->AddPartialFileToHashes(*(me->https->File)) == false)
  85             return 0;
  86       }
  87    }
  88    else if (me->https->Server->HeaderLine(line) == false)
  89       return 0;
  90
  91    return size*nmemb;
  92 }
  93
  94 size_t
  95 HttpsMethod::write_data(void *buffer, size_t size, size_t nmemb, void *userp)
  96 {
  97    HttpsMethod *me = (HttpsMethod *)userp;
  98    size_t buffer_size = size * nmemb;
  99    // we don't need to count the junk here, just drop anything we get as
 100    // we don't always know how long it would be, e.g. in chunked encoding.
 101    if (me->Server->JunkSize != 0)
 102       return buffer_size;
 103
 104    if(me->File->Write(buffer, buffer_size) != true)
 105       return 0;
 106
 107    if(me->Queue->MaximumSize > 0)
 108    {
 109       unsigned long long const TotalWritten = me->File->Tell();
 110       if (TotalWritten > me->Queue->MaximumSize)
 111       {
 112          me->SetFailReason("MaximumSizeExceeded");
 113          _error->Error("Writing more data than expected (%llu > %llu)",
 114                TotalWritten, me->Queue->MaximumSize);
 115          return 0;
 116       }
 117    }
 118
 119    if (me->Server->GetHashes()->Add((unsigned char const * const)buffer, buffer_size) == false)
 120       return 0;
 121
 122    return buffer_size;
 123 }
 124
 125 // HttpsServerState::HttpsServerState - Constructor                     /*{{{*/
 126 HttpsServerState::HttpsServerState(URI Srv,HttpsMethod * Owner) : ServerState(Srv, Owner), Hash(NULL)
 127 {
 128    TimeOut = _config->FindI("Acquire::https::Timeout",TimeOut);
 129    Reset();
 130 }
 131                                                                         /*}}}*/
 132 bool HttpsServerState::InitHashes(HashStringList const &ExpectedHashes) /*{{{*/
 133 {
 134    delete Hash;
 135    Hash = new Hashes(ExpectedHashes);
 136    return true;
 137 }
 138                                                                         /*}}}*/
 139 APT_PURE Hashes * HttpsServerState::GetHashes()                         /*{{{*/
 140 {
 141    return Hash;
 142 }
 143                                                                         /*}}}*/
 144
 145 void HttpsMethod::SetupProxy()                                          /*{{{*/
 146 {
 147    URI ServerName = Queue->Uri;
 148
 149    // Determine the proxy setting
 150    AutoDetectProxy(ServerName);
 151
 152    // Curl should never read proxy settings from the environment, as
 153    // we determine which proxy to use.  Do this for consistency among
 154    // methods and prevent an environment variable overriding a
 155    // no-proxy ("DIRECT") setting in apt.conf.
 156    curl_easy_setopt(curl, CURLOPT_PROXY, "");
 157
 158    // Determine the proxy setting - try https first, fallback to http and use env at last
 159    string UseProxy = _config->Find("Acquire::https::Proxy::" + ServerName.Host,
 160                                    _config->Find("Acquire::http::Proxy::" + ServerName.Host).c_str());
 161
 162    if (UseProxy.empty() == true)
 163       UseProxy = _config->Find("Acquire::https::Proxy", _config->Find("Acquire::http::Proxy").c_str());
 164
 165    // User want to use NO proxy, so nothing to setup
 166    if (UseProxy == "DIRECT")
 167       return;
 168
 169    if (UseProxy.empty() == false)
 170    {
 171       // Parse no_proxy, a comma (,) separated list of domains we don't want to use
 172       // a proxy for so we stop right here if it is in the list
 173       if (getenv("no_proxy") != 0 && CheckDomainList(ServerName.Host,getenv("no_proxy")) == true)
 174          return;
 175    } else {
 176       const char* result = getenv("https_proxy");
 177       // FIXME: Fall back to http_proxy is to remain compatible with
 178       // existing setups and behaviour of apt.conf.  This should be
 179       // deprecated in the future (including apt.conf).  Most other
 180       // programs do not fall back to http proxy settings and neither
 181       // should Apt.
 182       if (result == NULL)
 183          result = getenv("http_proxy");
 184       UseProxy = result == NULL ? "" : result;
 185    }
 186
 187    // Determine what host and port to use based on the proxy settings
 188    if (UseProxy.empty() == false)
 189    {
 190       Proxy = UseProxy;
 191       if (Proxy.Port != 1)
 192          curl_easy_setopt(curl, CURLOPT_PROXYPORT, Proxy.Port);
 193       curl_easy_setopt(curl, CURLOPT_PROXY, Proxy.Host.c_str());
 194       if (Proxy.User.empty() == false || Proxy.Password.empty() == false)
 195       {
 196          curl_easy_setopt(curl, CURLOPT_PROXYUSERNAME, Proxy.User.c_str());
 197          curl_easy_setopt(curl, CURLOPT_PROXYPASSWORD, Proxy.Password.c_str());
 198       }
 199    }
 200 }                                                                       /*}}}*/
 201 // HttpsMethod::Fetch - Fetch an item                                   /*{{{*/
 202 // ---------------------------------------------------------------------
 203 /* This adds an item to the pipeline. We keep the pipeline at a fixed
 204    depth. */
 205 bool HttpsMethod::Fetch(FetchItem *Itm)
 206 {
 207    struct stat SBuf;
 208    struct curl_slist *headers=NULL;
 209    char curl_errorstr[CURL_ERROR_SIZE];
 210    URI Uri = Itm->Uri;
 211    string remotehost = Uri.Host;
 212
 213    // TODO:
 214    //       - http::Pipeline-Depth
 215    //       - error checking/reporting
 216    //       - more debug options? (CURLOPT_DEBUGFUNCTION?)
 217
 218    curl_easy_reset(curl);
 219    SetupProxy();
 220
 221    maybe_add_auth (Uri, _config->FindFile("Dir::Etc::netrc"));
 222
 223    FetchResult Res;
 224    CURLUserPointer userp(this, &Res);
 225    // callbacks
 226    curl_easy_setopt(curl, CURLOPT_URL, static_cast<string>(Uri).c_str());
 227    curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, parse_header);
 228    curl_easy_setopt(curl, CURLOPT_WRITEHEADER, &userp);
 229    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
 230    curl_easy_setopt(curl, CURLOPT_WRITEDATA, this);
 231    // options
 232    curl_easy_setopt(curl, CURLOPT_NOPROGRESS, true);
 233    curl_easy_setopt(curl, CURLOPT_FILETIME, true);
 234    // only allow curl to handle https, not the other stuff it supports
 235    curl_easy_setopt(curl, CURLOPT_PROTOCOLS, CURLPROTO_HTTPS);
 236    curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS, CURLPROTO_HTTPS);
 237
 238    // SSL parameters are set by default to the common (non mirror-specific) value
 239    // if available (or a default one) and gets overload by mirror-specific ones.
 240
 241    // File containing the list of trusted CA.
 242    string cainfo = _config->Find("Acquire::https::CaInfo","");
 243    string knob = "Acquire::https::"+remotehost+"::CaInfo";
 244    cainfo = _config->Find(knob.c_str(),cainfo.c_str());
 245    if(cainfo.empty() == false)
 246       curl_easy_setopt(curl, CURLOPT_CAINFO,cainfo.c_str());
 247
 248    // Check server certificate against previous CA list ...
 249    bool peer_verify = _config->FindB("Acquire::https::Verify-Peer",true);
 250    knob = "Acquire::https::" + remotehost + "::Verify-Peer";
 251    peer_verify = _config->FindB(knob.c_str(), peer_verify);
 252    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, peer_verify);
 253
 254    // ... and hostname against cert CN or subjectAltName
 255    bool verify = _config->FindB("Acquire::https::Verify-Host",true);
 256    knob = "Acquire::https::"+remotehost+"::Verify-Host";
 257    verify = _config->FindB(knob.c_str(),verify);
 258    int const default_verify = (verify == true) ? 2 : 0;
 259    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, default_verify);
 260
 261    // Also enforce issuer of server certificate using its cert
 262    string issuercert = _config->Find("Acquire::https::IssuerCert","");
 263    knob = "Acquire::https::"+remotehost+"::IssuerCert";
 264    issuercert = _config->Find(knob.c_str(),issuercert.c_str());
 265    if(issuercert.empty() == false)
 266       curl_easy_setopt(curl, CURLOPT_ISSUERCERT,issuercert.c_str());
 267
 268    // For client authentication, certificate file ...
 269    string pem = _config->Find("Acquire::https::SslCert","");
 270    knob = "Acquire::https::"+remotehost+"::SslCert";
 271    pem = _config->Find(knob.c_str(),pem.c_str());
 272    if(pem.empty() == false)
 273       curl_easy_setopt(curl, CURLOPT_SSLCERT, pem.c_str());
 274
 275    // ... and associated key.
 276    string key = _config->Find("Acquire::https::SslKey","");
 277    knob = "Acquire::https::"+remotehost+"::SslKey";
 278    key = _config->Find(knob.c_str(),key.c_str());
 279    if(key.empty() == false)
 280       curl_easy_setopt(curl, CURLOPT_SSLKEY, key.c_str());
 281
 282    // Allow forcing SSL version to SSLv3 or TLSv1 (SSLv2 is not
 283    // supported by GnuTLS).
 284    long final_version = CURL_SSLVERSION_DEFAULT;
 285    string sslversion = _config->Find("Acquire::https::SslForceVersion","");
 286    knob = "Acquire::https::"+remotehost+"::SslForceVersion";
 287    sslversion = _config->Find(knob.c_str(),sslversion.c_str());
 288    if(sslversion == "TLSv1")
 289      final_version = CURL_SSLVERSION_TLSv1;
 290    else if(sslversion == "SSLv3")
 291      final_version = CURL_SSLVERSION_SSLv3;
 292    curl_easy_setopt(curl, CURLOPT_SSLVERSION, final_version);
 293
 294    // CRL file
 295    string crlfile = _config->Find("Acquire::https::CrlFile","");
 296    knob = "Acquire::https::"+remotehost+"::CrlFile";
 297    crlfile = _config->Find(knob.c_str(),crlfile.c_str());
 298    if(crlfile.empty() == false)
 299       curl_easy_setopt(curl, CURLOPT_CRLFILE, crlfile.c_str());
 300
 301    // cache-control
 302    if(_config->FindB("Acquire::https::No-Cache",
 303         _config->FindB("Acquire::http::No-Cache",false)) == false)
 304    {
 305       // cache enabled
 306       if (_config->FindB("Acquire::https::No-Store",
 307                 _config->FindB("Acquire::http::No-Store",false)) == true)
 308          headers = curl_slist_append(headers,"Cache-Control: no-store");
 309       stringstream ss;
 310       ioprintf(ss, "Cache-Control: max-age=%u", _config->FindI("Acquire::https::Max-Age",
 311                 _config->FindI("Acquire::http::Max-Age",0)));
 312       headers = curl_slist_append(headers, ss.str().c_str());
 313    } else {
 314       // cache disabled by user
 315       headers = curl_slist_append(headers, "Cache-Control: no-cache");
 316       headers = curl_slist_append(headers, "Pragma: no-cache");
 317    }
 318    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
 319
 320    // speed limit
 321    int const dlLimit = _config->FindI("Acquire::https::Dl-Limit",
 322                 _config->FindI("Acquire::http::Dl-Limit",0))*1024;
 323    if (dlLimit > 0)
 324       curl_easy_setopt(curl, CURLOPT_MAX_RECV_SPEED_LARGE, dlLimit);
 325
 326    // set header
 327    curl_easy_setopt(curl, CURLOPT_USERAGENT,
 328         _config->Find("Acquire::https::User-Agent",
 329                 _config->Find("Acquire::http::User-Agent",
 330                         "Debian APT-CURL/1.0 (" PACKAGE_VERSION ")").c_str()).c_str());
 331
 332    // set timeout
 333    int const timeout = _config->FindI("Acquire::https::Timeout",
 334                 _config->FindI("Acquire::http::Timeout",120));
 335    curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, timeout);
 336    //set really low lowspeed timeout (see #497983)
 337    curl_easy_setopt(curl, CURLOPT_LOW_SPEED_LIMIT, DL_MIN_SPEED);
 338    curl_easy_setopt(curl, CURLOPT_LOW_SPEED_TIME, timeout);
 339
 340    // set redirect options and default to 10 redirects
 341    curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, AllowRedirect);
 342    curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 10);
 343
 344    // debug
 345    if (Debug == true)
 346       curl_easy_setopt(curl, CURLOPT_VERBOSE, true);
 347
 348    // error handling
 349    curl_errorstr[0] = '\0';
 350    curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 351
 352    // If we ask for uncompressed files servers might respond with content-
 353    // negotiation which lets us end up with compressed files we do not support,
 354    // see 657029, 657560 and co, so if we have no extension on the request
 355    // ask for text only. As a sidenote: If there is nothing to negotate servers
 356    // seem to be nice and ignore it.
 357    if (_config->FindB("Acquire::https::SendAccept", _config->FindB("Acquire::http::SendAccept", true)) == true)
 358    {
 359       size_t const filepos = Itm->Uri.find_last_of('/');
 360       string const file = Itm->Uri.substr(filepos + 1);
 361       if (flExtension(file) == file)
 362          headers = curl_slist_append(headers, "Accept: text/*");
 363    }
 364
 365    // if we have the file send an if-range query with a range header
 366    if (stat(Itm->DestFile.c_str(),&SBuf) >= 0 && SBuf.st_size > 0)
 367    {
 368       std::string Buf;
 369       strprintf(Buf, "Range: bytes=%lli-", (long long) SBuf.st_size);
 370       headers = curl_slist_append(headers, Buf.c_str());
 371       strprintf(Buf, "If-Range: %s", TimeRFC1123(SBuf.st_mtime).c_str());
 372       headers = curl_slist_append(headers, Buf.c_str());
 373    }
 374    else if(Itm->LastModified > 0)
 375    {
 376       curl_easy_setopt(curl, CURLOPT_TIMECONDITION, CURL_TIMECOND_IFMODSINCE);
 377       curl_easy_setopt(curl, CURLOPT_TIMEVALUE, Itm->LastModified);
 378    }
 379
 380    // go for it - if the file exists, append on it
 381    File = new FileFd(Itm->DestFile, FileFd::WriteAny);
 382    Server = CreateServerState(Itm->Uri);
 383    if (Server->InitHashes(Itm->ExpectedHashes) == false)
 384       return false;
 385
 386    // keep apt updated
 387    Res.Filename = Itm->DestFile;
 388
 389    // get it!
 390    CURLcode success = curl_easy_perform(curl);
 391
 392    // If the server returns 200 OK but the If-Modified-Since condition is not
 393    // met, CURLINFO_CONDITION_UNMET will be set to 1
 394    long curl_condition_unmet = 0;
 395    curl_easy_getinfo(curl, CURLINFO_CONDITION_UNMET, &curl_condition_unmet);
 396
 397    File->Close();
 398    curl_slist_free_all(headers);
 399
 400    // cleanup
 401    if (success != 0)
 402    {
 403       _error->Error("%s", curl_errorstr);
 404       return false;
 405    }
 406
 407    // server says file not modified
 408    if (Server->Result == 304 || curl_condition_unmet == 1)
 409    {
 410       unlink(File->Name().c_str());
 411       Res.IMSHit = true;
 412       Res.LastModified = Itm->LastModified;
 413       Res.Size = 0;
 414       URIDone(Res);
 415       return true;
 416    }
 417    Res.IMSHit = false;
 418
 419    if (Server->Result != 200 && // OK
 420          Server->Result != 206 && // Partial
 421          Server->Result != 416) // invalid Range
 422    {
 423       char err[255];
 424       snprintf(err, sizeof(err) - 1, "HttpError%i", Server->Result);
 425       SetFailReason(err);
 426       _error->Error("%s", err);
 427       // unlink, no need keep 401/404 page content in partial/
 428       unlink(File->Name().c_str());
 429       return false;
 430    }
 431
 432    // invalid range-request
 433    if (Server->Result == 416)
 434    {
 435       unlink(File->Name().c_str());
 436       delete File;
 437       Redirect(Itm->Uri);
 438       return true;
 439    }
 440
 441    struct stat resultStat;
 442    if (unlikely(stat(File->Name().c_str(), &resultStat) != 0))
 443    {
 444       _error->Errno("stat", "Unable to access file %s", File->Name().c_str());
 445       return false;
 446    }
 447    Res.Size = resultStat.st_size;
 448
 449    // Timestamp
 450    curl_easy_getinfo(curl, CURLINFO_FILETIME, &Res.LastModified);
 451    if (Res.LastModified != -1)
 452    {
 453       struct timeval times[2];
 454       times[0].tv_sec = Res.LastModified;
 455       times[1].tv_sec = Res.LastModified;
 456       times[0].tv_usec = times[1].tv_usec = 0;
 457       utimes(File->Name().c_str(), times);
 458    }
 459    else
 460       Res.LastModified = resultStat.st_mtime;
 461
 462    // take hashes
 463    Res.TakeHashes(*(Server->GetHashes()));
 464
 465    // keep apt updated
 466    URIDone(Res);
 467
 468    // cleanup
 469    delete File;
 470
 471    return true;
 472 }
 473                                                                         /*}}}*/
 474 // HttpsMethod::Configuration - Handle a configuration message          /*{{{*/
 475 bool HttpsMethod::Configuration(string Message)
 476 {
 477    if (ServerMethod::Configuration(Message) == false)
 478       return false;
 479
 480    AllowRedirect = _config->FindB("Acquire::https::AllowRedirect",
 481         _config->FindB("Acquire::http::AllowRedirect", true));
 482    Debug = _config->FindB("Debug::Acquire::https",false);
 483
 484    return true;
 485 }
 486                                                                         /*}}}*/
 487 ServerState * HttpsMethod::CreateServerState(URI uri)                   /*{{{*/
 488 {
 489    return new HttpsServerState(uri, this);
 490 }
 491                                                                         /*}}}*/
 492
 493 int main()
 494 {
 495    setlocale(LC_ALL, "");
 496
 497    HttpsMethod Mth;
 498    curl_global_init(CURL_GLOBAL_SSL) ;
 499
 500    return Mth.Run();
 501 }
 502